Dual jaw crusher



Aug. 25, 1964 H. c. POLLITZ DUAL JAwcRusHER Filed April 3, 1963 FIG I'NVENTOR HAROLD c. POLLITZ FIG 2 ATTORNEY Aug. 25, 1964 H. C. POLLITZ DUAL JAW CRUSHER Filed April 3, 1963 2 Sheets-Sheet 2 FIG 4 INVENTOR.

' HAROLD C. POLLITZ ATTORNEY United States Patent 3,145,938 DUAL JAW CRUSHER Harold C. Pollitz, Cedar Rapids, Iowa, assignor to Iowa Manufacturing Company, Cedar Rapids, Iowa Filed Apr. 3, 1963, Ser. No. 270,303 2 Claims. (Cl. 241-140) The present invention concerns crushers of the dual jaw type and is particularly directed to means to impart a substantially linear motion to the lower portion of the movable jaw thereof.

In crushers of the jaw type it is desirable to have the motion of the lower portion of the moving jaw or pitman, to and from the stationary jaw or jaws, as nearly linear as possible instead of orbital. This is because the greatest crushing efficiency is achieved by a linear motion of one jaw relative to the other, and inasmuch as the greatest portion of the crushing action is achieved between the lower ends of the stationary and movable jaws, the throat of the crusher, the jaw motion should be as nearly linear as possible in that area particularly. This is relatively easily accomplished in crushers of the single jaw type in which the eccentric drive is applied to the upper end of the pitman where little crushing action is achieved anyway, and in which the largely linear motion of the lower end of the jaw, where the greatest portion of the crushing action occurs, is imparted by the customary toggle plate or similar connection extending from behind the lower end of the pitman to the crusher frame.

In a dual jaw crusher, however, in which both faces of the pitman are confronted by the opposing stationary jaws, it is diificult, if not impossible, to fit in a suitable toggle connection owing to the intrusion of the stationary jaws between the lower end of the pitman and the crusher frame. Consequently the practice has been instead to locate the eccentric drive at the lower end of the pitman and provide a toggle plate or plates, or other suitable structure, between the upper end of the pitman and the frame, as shown, for instance, in US. Patents 2,595,219 and 2,670,141 to Anderson. Not only does this result in additional complication and expense, but particularly it reduces crushing efiiciency because, as mentioned, the motion of the lower end of the pitman is therefore orbital rather than the preferable linear motion.

Accordingly, it is the primary object of the present invention to provide a dual jaw crusher in which the motion of the lower end of the movable jaw or pitman is substantially a linear, reciprocating movement.

Another object of the present invention is the provision of a jaw crusher of the dual type in which an eccentric movement is imparted to the upper portion of the pitman and in which means are provided to impart a substantially linear, reciprocating movement to the lower end of the pitman between the adjacent opposed stationary jaws.

A further object of the present invention is to provide rugged, effective and inexpensive means connecting the lower end of the pitman of dual jaw crusher to the crusher frame so that said lower end is given a substantially linear, reciprocating movement between the opposed stationary jaws.

Essentially the present invention locates the eccentric drive of the pitman at its upper end, but employs a pair of link bars pivotally connected at their corresponding ends to the lower end of the pitman by means of a stub axle or trunnion extending from each end of the pitman through and beyond the adjacent crusher wall. The link bars are thus located outside the crusher frame and extend laterally from their respective pitman trunnions alongside their respective crusher frame walls and are pivotally attached at their respective remaining ends to the crusher frame itself. Suitable direction and amplitude of movement of the lower end of the pitman are achieved by proper adjustment of the lengths of the link bars and the location of their fixed pivots on the crusher frame. In. this manner the intruding presence of the stationary jaws on each side of the pitman is circumvented on the one hand, and on the other hand, the desirable linear motion of the pitmans lower end is achieved in a rugged and simple manner.

Other objects, features and advantages of the present invention will be apparent from the'preferred forms thereof hereafter described, read in conjunction with the drawings, in which:

FIGURE 1 is a somewhat diagrammatic side elevation, partly in section along the line 11 of FIGURE 2, of a dual jaw crusher according to the present invention;

FIGURE 2 is a plan view of the crusher shown in FIGURE 1;

FIGURE 3 is a diagrammatic representation illustrating the jaw movements according to the present invention; and

FIGURE 4 is similar to FIGURE 1 but illustrates another preferred form of the present invention.

The structure of the crusher illustrated in the drawings is basically quite conventional and employs a frame of generally rectangular section having parallel end walls 10 and 11 and parallel side walls 12 and 13. Disposed atop and spanning the latter centrally between end walls 10 and 11, is a suitable drive shaft 14 journalled in side bearings 15 just inboard of the respective ends of shaft 14 to which in turn are fixed flywheels 16, one of which is driven by appropriate means (not shown). The two portions of drive shaft 14 just inboard of side bearings 15 are provided with a pair of eccentric journals 17 (only one of which is shown in the figures) about which in turn is mounted in bearings the upper end of movable jaw or pitman 18. The latter depends from journals 17 and extends transversely between sidewalls 12 and 13, being provided upon its opposite lateral faces with suitable jaw plates 19 and 19'. For further details of the mounting of pitman 18 see, for example, U.S. Patent 3,061,317. A pair of conventional stationary jaws 20 and 20', provided with suitable jaw plates 21 and 21, are utilized, each being spaced laterally from one of jaw plates 19, 19 and pivotally mounted at its upper end at 22, 22, respectively, between sidewalls 12 and 13 adjacent its respective one of end walls 10 and 11. Each jaw 20, 20' and jaw plate 21, 21 extends downwardly and convergingly toward its respective opposing one of jaw plates 19, 19, the lower ends of each pair of opposing jaw plates 19, 21, and 19', 21', being closely spaced from one another to form, together with sidewalls 12 and 13, the throats of a pair of crushing cavities 23 and 23'. The lower ends of jaw plates 21, 21 are adjustably maintained in position relative to jaw plates 19, 19, by any suitable means. That illustrated comprises a pair of toggle plates 24, 24, centrally weakened in the customary manner in order to fracture in case of overloads on the crusher, extending transversely between sidewalls 12 and 13 and located at one end in suitable seats upon the rear faces of jaws 20, 20'. Wedges or shims 25, 25 or other suitable means, are interposed in turn between the other end of toggle plates 24, 24' and end walls 10 and 11, respectively, in order to permit adjustment of jaw plates 21, 21 about pivots 22, 22 relative to jaw plates 19, 19, thus varying the threats of crushing cavities 23, 23 and consequently the ultimate size to which the crushed material will be reduced. Appropriate means, such as heavy, extensible coil springs 26, 26, maintain jaws 20, 29' in engagement with toggle plates 24, 24.

Pitman 18 is provided midway between and adjacent the lower end of jaw plates 19, 19' with trunnions 30, 30, extending on a common axis parallel to the axis of eccentric journals 17 from each transverse end of pitman 18 outwards beyond sidewalls 12 and 13 through appropriate apertures 31 therein, only the one in side wall 13 being illustrated. A second pair of trunnions 32, 32' are fixed upon the outer faces of sidewalls 12 and 13 and extend outwardly therefrom along a common axis parallel to the axis of trunnions 30, 30. The axis of trunnions 32, 32 is disposed below and laterally of the axis of trunnions 3t), 30' so that the included angle between a plane through the axis of trunnions 3t), 30 and the axis of eccentric journals 17 and a plane through the axes of trunnions 30, 30 and trunnions 32, 32' is greater than 90 but less than 180 degrees. These two planes are denoted by the lines AB, BC, in FIGURE 3, point C representing the axis of eccentric journals 17 at one of the two positions on its circle of eccentricity 2 (shown disproportionately large for purposes of clarity) where line BC intersects the axis of drive shaft 14. Finally, a pair of link bars 33, 33, of generally rectangular section, are pivoted to the respective pairs of trunnions, 30, 32, and 30, 32, on each side of the crusher. Link bars 33, 33' may be enclosed, if desired, by suitable housings (not shown) secured to the respective outer faces of sidewalls l2 and 13.

FIGURE 3 illustrates the approximate movements of jaw plates 19, 19' during crusher operation. The upper edges of the latter follow an orbital path of the nature denoted by ovals or loops 4t 40', respectively, owing to the gyration of the upper end of pitman 18 about the fixed axis of drive shaft 14. Midway down jaws 19, 19' the movement is still largely orbital but the orbits, 41, 41', are flatter having greater lateral vertical components. At the lower edges of jaw plates 19, 19 the vertical component of orbits 42, 42 is nearly non-existent and the movement therefore is substantially linear, reciprocating transversely between the respective opposing stationary jaw plates 21, 21.

If the axis A of trunnions 32, 32' is raised toward the level of axis B of trunnions 30, 3t), the lateral throw or aggressiveness of pitman 18 is reduced with respect to both stationary jaws and 20 until, when axis A is level with axis B, the aggressiveness is practically nil. Thus angle ABC must be greater than 90 but less than 180 degrees. Shortening the distance between axis A and B, and thus the length of link bars 33, 33, along any line AB tends to increase the aggressiveness of the crusher with respect particularly to the stationary jaw 20 near axis A with relatively lesser change in aggressiveness with respect to the more distant stationary jaw 29. Thus the most suitable length for link bars 33, 33 and locations of trunnions 32, 32' relative to the distance BC and eccentricity e of pitman 18 can be determined by those of skill in the art. The only limiting factor is that the location of axis A and the distance between it and axis B must be such that the distance between axis A and any point C on the circle of ececntricty e is at all times less than the sum of distances AB and BC in order for the crusher to be operative.

In the alternate preferred form of the invention illustrated in FIGURE 4, the axis of trunnions 50 fixed to side walls 12, 13 and pivoted to link bars 51 (only one of trunnions 50 and link bars 51 being shown) is located at A above the level of axis B so that the angle ABC is less than 90 degrees. The movement of pitman 18 resulting therefrom is substantially the same as in the embodiment of FIGURES 1 through 3, the other structure of both embodiments being identical and referred to by identical reference numerals. However, raising axis A and thus decreasing angle ABC, increases the aggressiveness of the crusher in much the same manner as lowering axis A and increasing angle ABC. Likewise, increasing angle ABC by moving axis A toward the level of axis B decreases the aggressiveness of the crusher. Thus angle A'BC must be greater than zero but less than degrees.

While the present invention has been described with reference to particular embodiments and detailed descriptive language has been used, it is not so limited. Instead the following claims are to be read as encompassing such modifications and adaptations of the invention as would ordinarily occur to one skilled in the art.

I claim:

1. In a dual jaw crusher having a pair of spaced, upright frame walls, a generally upright movable jaw provided with a pair of oppositely facing, generally upright crushing surfaces fixed thereon extending transversely between said walls, said movable jaw being suspended adjacent its upper end for gyratory movement on an axis having an eccentric movement about a fixed axis extending transversely between said walls, a pair of stationary jaws, each having a crushing surface fixed thereon and disposed transversely between said walls in opposed, spaced relation to substantially the entire expanse of one of said movable jaw surfaces, each pair of opposed stationary and movable jaw surfaces converging downwardly in order to define together with said frame walls a crushing cavity at each side of said movable jaw, the improvement comprising means to impart a reciprocating, substantially linear movement to the lower end of each of said movable jaw surfaces along a path parallel to said fixed axis and transversely of both of said stationary jaw surfaces during gyration of the upper end of said movable jaw, said means comprising a pair of rigid link bars, each pivoted at one end thereof to one transverse end of said movable jaw about a first common axis disposed parallel to said fixed axis adjacent the lower ends of said movable crushing surfaces and at the other end thereof to the adjacent one of said frame walls about a second common axis laterally disposed from and parallel to said first axis, the distance between said first and second axis together with the distance between said first axis and any point upon the path of said eccentric axis being greater than the distance between any such point and said second axis during operative movement of said movable jaw, and the included angle between a plane through said fixed axis and said first axis and a plane through the latter and said second axis being [-(90ia)] degrees, where a is an angle greater than zero but less than 90 degrees. l

2. The device of claim 1 wherein said link bars are disposed along and outside of said frame walls, said pivots of said second axis extending outwardly from said frame walls and said pivots of said first axis extending from the transverse end of said movable jaw outwardly from said frame walls through apertures operatively disposed therein.

References Cited in the file of this patent UNITED STATES PATENTS 2,034,401 Kraemer Mar. 17, 1936 2,626,759 Barber et al. Jan. 27, 1953 2,998,936 Gruender Sept. 5, 1961 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 145,938 August 25, 1964 Harold C. Pollitz hat error appears in the above numbered pat- 'It is hereby certified t ent req'liring correction and that the said Letters Patentshould read as corrected below Column 3, line 37, after "lateral" insert than v; line 61, for "ececntricty" read eccentricity Signed and sealed this 22nd day of December 1964.

LfiEAL) Attest:

@DWARD J BRENNER:

Commissioner of Patents ERNEST W; SWIDER A1 testing Officer 

1. IN A DUAL JAW CRUSHER HAVING A PAIR OF SPACED, UPRIGHT FRAME WALLS, A GENERALLY UPRIGHT MOVABLE JAW PROVIDED WITH A PAIR OF OPPOSITELY FACING, GENERALLY UPRIGHT CRUSHING SURFACES FIXED THEREON EXTENDING TRANSVERSELY BETWEEN SAID WALLS, SAID MOVABLE JAW BEING SUSPENDED ADJACENT ITS UPPER END FOR GYRATORY MOVEMENT ON AN AXIS HAVING AN ECCENTRIC MOVEMENT ABOUT A FIXED AXIS EXTENDING TRANSVERSELY BETWEEN SAID WALLS, A PAIR OF STATIONARY JAWS, EACH HAVING A CRUSHING SURFACE FIXED THEREON AND DISPOSED TRANSVERSELY BETWEEN SAID WALLS IN OPPOSED, SPACED RELATION TO SUBSTANTIALLY THE ENTIRE EXPANSE OF ONE OF SAID MOVABLE JAW SURFACES, EACH PAIR OF OPPOSED STATIONARY AND MOVABLE JAW SURFACES, CONVERGING DOWNWARDLY IN ORDER TO DEFINE TOGETHER WITH SAID FRAME WALLS A CRUSHING CAVITY AT EACH SIDE OF SAID MOVABLE JAW, THE IMPROVEMENT COMPRISING MEANS TO IMPART A RECIPROCATING, SUBSTANTIALLY LINEAR MOVEMENT TO THE LOWER END OF EACH OF SAID MOVABLE JAW SURFACES ALONG A PATH PARALLEL TO SAID FIXED AXIS AND TRANSVERSELY OF BOTH OF SAID STATIONARY JAW SURFACE DURING GYRATION OF THE UPPER END OF SAID MOVABLE JAW, SAID MEANS COMPRISING A PAIR OF RIGID LINK BARS, EACH PIVOTED AT ONE END THEREOF TO ONE TRANSVERSE END OF SAID MOVABLE JAW ABOUT A FIRST COMMON AXIS DISPOSED PARALLEL TO SAID FIXED AXIS ADJACENT THE LOWER ENDS OF SAID MOVABLE CRUSHING SURFACES AND AT THE OTHER END THEREOF TO THE ADJACENT ONE OF SAID FRAME WALLS ABOUT A SECOND COMMON AXIS LATERALLY DISPOSED FROM AND PARALLEL TO SAID FIRST AXIS, THE DISTANCE BETWEEN SAID FIRST AND SECOND AXIS TOGETHER WITH THE DISTANCE BETWEEN SAID FIRST AXIS AND ANY POINT UPON THE PATH OF SAID ECCENTRIC AXIS BEING GREATER THAN THE DISTANCE BETWEEN ANY SUCH POINT AND SAID SECTHAN THE DISTANCE BETWEEN ANY SUCH POINT AND SAID SECOND AXIS DURING OPERATIVE MOVEMENT OF SAID MOVABLE JAW, AND THE INCLUDED ANGLE BETWEEN A PLANE THROUGH SAID FIXED AXIS AND SAID FIRST AXIS AND A PLANE THROUGH THE LATTER AND SAID SECOND AXIS BEING (180-(90$A)) DEGREES, WHERE A IS AN ANGLE GREATER THAN ZERO BUT LESS THAN 90 DEGREES. 